WASHINGTON — Space shuttle landings were supposed to be routine. And until Feb. 1, 2003, they were — at least to most Americans.

Much like the 1986 Challenger disaster, that expectation of normalcy was a big reason why Columbia's disintegration over the southwestern United States so shocked and horrified the nation.

Adding to that agony was the eventual realization that, once again, human failings were a root cause of why seven astronauts were dead. Their names: Commander Rick Husband, pilot William McCool, Michael Anderson, Kalpana Chawla, David Brown, Laurel Clark, and Ilan Ramon of Israel.

Officially, the accident was caused by a briefcase-sized chunk of insulating foam that came away from the shuttle's external fuel tank and punched a hole in the orbiter's left wing 81.9 seconds after launch Jan. 16. NASA engineers had long ignored foam coming off the tank — believing it was essentially harmless — but the damaged wing could not protect the orbiter from the searing heat of re-entry.

In the months that followed, NASA was forced to re-examine nearly every facet of its operation, from launch safety to how employees talked to one another. And a special investigation board appointed to determine the cause of the tragedy came to this stunning conclusion:

"We are convinced that the management practices overseeing the Space Shuttle Program were as much a cause of the accident as the foam that struck the left wing."

Ultimately, shuttles flew again, and — in 22 missions — completed construction of the International Space Station. On July 21, 2011, the final flight of Atlantis ended the program. The three remaining shuttles are now museum pieces.

But 10 years later, those closest to the Columbia tragedy said the same risks remain. Space travel is still dangerous. Policymakers in Washington continue to ask NASA to do too much with too little. And basic human weaknesses such as ego and apathy are ever-present.

Rodney Rocha, NASA engineer

Of all the pain caused by the Columbia disaster, what hurt NASA workers most was the determination by accident investigators that NASA's safety culture was "as much a cause of the accident" as the foam that led to the orbiter's destruction.

Rodney Rocha was an outspoken example of how the agency's "culture" failed. The engineer repeatedly tried to persuade NASA managers to get telescopic pictures of Columbia's wing before re-entry to better understand the damage.

Rocha was ignored by managers, who couldn't believe a piece of insulating material — the consistency of Styrofoam — could crack open the orbiter's wing.

Ten years later, Rocha said he still regrets not "breaking the door down" to force NASA higher-ups to get those pictures and maybe develop a last-ditch rescue plan.

But Rocha, still with NASA, said that since the disaster, the agency listens more to concerns raised by its frontline engineers.

A key example, he said, was the 2009 mission to repair the Hubble Space Telescope. Because the telescope was too far from the space station for the shuttle to use it as safe haven, the only way to rescue the astronauts in case they got in trouble was to send another orbiter.

Rocha said NASA managers initially underestimated the difficulty of transferring astronauts from a stranded orbiter to a rescue orbiter — until he and other engineers stepped forward.

"I think it illustrates the change — and I hate to use the word 'culture' — but a [new] openness to alternate technical views," he said.

The result, he said, was that NASA developed better plans to prepare for a rescue mission, which ultimately wasn't necessary.

Rocha is asked to speak at NASA centers a few times a year to talk about lessons learned from Columbia. His message to managers: Listen up. And to workers: Speak out.

"So you get your hand slapped. You get chastised," he said. "Then say: 'Can I file [my concerns] anyway?' "

Dr. Jonathan Clark, grieving husband

Of all the questions asked in the aftermath of Columbia, Dr. Jonathan Clark — husband of mission specialist Laurel Clark — said it's one from their son, Iain, that keeps ringing in his head.

Just 8 at the time of the accident, Iain wanted to know why his mom didn't bail out of the shuttle as it broke apart.

Though investigators would conclude that crew survival was impossible — given the orbiter's design and its speed at break-up — the question has nagged at Clark, a former NASA flight surgeon and now an associate professor of space medicine at Baylor University.

So in the decade since, he has devoted himself to finding ways to improve the safety of astronauts and adventurers.

"You have got to find ways to turn badness into goodness. You have to," he said. "It's the only way you get through this."